diff --git a/lib/core/common.py b/lib/core/common.py
index 695ab6696..e877dde50 100644
--- a/lib/core/common.py
+++ b/lib/core/common.py
@@ -3893,7 +3893,7 @@ def asciifyUrl(url, forceQuote=False):
         #     urllib.quote(s.replace('%', '')) != s.replace('%', '')
         # which would trigger on all %-characters, e.g. "&".
         if getUnicode(s).encode("ascii", "replace") != s or forceQuote:
-            return urllib.quote(s.encode(UNICODE_ENCODING), safe=safe)
+            return urllib.quote(s.encode(UNICODE_ENCODING) if isinstance(s, unicode) else s, safe=safe)
         return s
 
     username = quote(parts.username, '')
diff --git a/lib/core/settings.py b/lib/core/settings.py
index 9ff6ff243..d029fe5f3 100644
--- a/lib/core/settings.py
+++ b/lib/core/settings.py
@@ -19,7 +19,7 @@ from lib.core.enums import DBMS_DIRECTORY_NAME
 from lib.core.enums import OS
 
 # sqlmap version (<major>.<minor>.<month>.<monthly commit>)
-VERSION = "1.2.4.20"
+VERSION = "1.2.4.21"
 TYPE = "dev" if VERSION.count('.') > 2 and VERSION.split('.')[-1] != '0' else "stable"
 TYPE_COLORS = {"dev": 33, "stable": 90, "pip": 34}
 VERSION_STRING = "sqlmap/%s#%s" % ('.'.join(VERSION.split('.')[:-1]) if VERSION.count('.') > 2 and VERSION.split('.')[-1] == '0' else VERSION, TYPE)
diff --git a/txt/checksum.md5 b/txt/checksum.md5
index f80319e4f..9055570eb 100644
--- a/txt/checksum.md5
+++ b/txt/checksum.md5
@@ -27,7 +27,7 @@ c7443613a0a2505b1faec931cee2a6ef  lib/controller/handler.py
 1e5532ede194ac9c083891c2f02bca93  lib/controller/__init__.py
 b1990c7805943f0c973a853bba981d96  lib/core/agent.py
 fd8f239e259afaf5f24bcf34a0ad187f  lib/core/bigarray.py
-9e88889d6fd9cb9a17e467b72ec30305  lib/core/common.py
+f42e346d33199b4f663cff6efe2be775  lib/core/common.py
 0d082da16c388b3445e656e0760fb582  lib/core/convert.py
 9f87391b6a3395f7f50830b391264f27  lib/core/data.py
 72016ea5c994a711a262fd64572a0fcd  lib/core/datatype.py
@@ -46,7 +46,7 @@ c9a56e58984420a5abb7a3f7aadc196d  lib/core/optiondict.py
 0c3eef46bdbf87e29a3f95f90240d192  lib/core/replication.py
 a7db43859b61569b601b97f187dd31c5  lib/core/revision.py
 fcb74fcc9577523524659ec49e2e964b  lib/core/session.py
-551c1eba020f0319b9206236b1aeac00  lib/core/settings.py
+2f9027a2ceb362b21119d335bbcdaa4c  lib/core/settings.py
 0dfc2ed40adf72e302291f6ecd4406f6  lib/core/shell.py
 a7edc9250d13af36ac0108f259859c19  lib/core/subprocessng.py
 a35efa7bec9f1e6cedf17c9830a79241  lib/core/target.py